You can apply to the course under the available student place scheme at Aarhus BSS in the spring and the autumn. If you are applying to the available student place scheme at more than one faculty, you must apply to each faculty. http://www.au.dk/evu/uddannelsestyper/tompladsordningen/
Application deadlines:
Courses in the spring: 1 November
Courses in the autumn: 1 May
Applications will be accepted starting approximately one month before the deadline. You must apply online from this website.
You can expect a reply no later than mid-August/early February, depending on when you submitted your application. On some courses, you will not be informed about admission until the semester starts, as the board of studies does not know whether there are any available student places until then.